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In vivo evaluation of femoral blood flow measured with magnetic resonance

Quantitative measurements of blood flow based on magnetic resonance imaging (MRI) using conventional multiple spin echo sequences were evalutated in vivo in healthy young volunteers. Blood flow was measured using MRI in the femoral vein. The initial slope of the multiple spin echo decay curve, corrected for the T2 decay of non-flowing blood was used to calculate the blood flow. As a reference, the

Magnetic resonance imaging and aneurysm clips. Magnetic properties and image artifacts

The magnetic properties of 12 different types of aneurysm clip were investigated in order to identify which clips allow postoperative magnetic resonance (MR) imaging without risk. Clip-induced MR artifacts were also quantitatively studied using a geometrical phantom. Nonferromagnetic aneurysm clips like the Yasargil Phynox, Sugita Elgiloy, and Vari-Angle McFadden clips do not appear to contraindic

Determination of flow velocities from magnetic resonance multiple spin-echo images : A phantom study

The purpose of this study was to evaluate a method for the quantification of through-plane flow velocities by magnetic resonance imaging (MRI) from the flow characteristics of conventional multiple spin-echo (MSE) signals. Simulated inflow-outflow-dependent signals, as well as images of a flow phantom were generated and the logarithm of the flow-dependent signal value was plotted against echo time

Correlations between histopathologic white matter changes and proton MR relaxation times in dementia.

Our previous studies have shown that incomplete white matter infarctions are common in senile dementia of the Alzheimer type. To visualize and interpret these changes on magnetic resonance imaging (MRI), knowledge of MR relaxation times associated with this histopathology is important. The proton MR relaxation times T1 and T2 were determined in vitro for 3 groups of specimens. Fifty specimens of n

Quantitative study of flow dependence in NMR images at low flow velocities

A basic theoretical model that describes the effects of flow in and out of the imaging plane in nuclear magnetic resonance (NMR) images, obtained with the standard pulse sequences single spin echo, multiple spin echo, and inversion recovery, is presented. Theoretically calculated signal values are compared with experimental results obtained from single-slice images of a flow phantom for variable f

Tumours of the central nervous system. Proton magnetic resonance relaxation times T1 and T2 and histopathologic correlates

Proton MR relaxation times T1 and T2 were determined in vitro in 136 small specimens of astrocytomas grades I-IV, of oligodendrogliomas, metastases of adenocarcinomas, meningiomas and acoustic neuromas. In addition, 7 samples of peritumoural white matter were analysed. The analysed specimens were studied microscopically in their entirety regarding tumour type and occurrence of necrosis and non-tum

Peer Gender and Mental Health

Adolescent mental health is key for later well-being. Yet, causal evidence on environmental drivers of adolescent mental health is scant. We study how an important classroom feature---the gender composition in compulsory-school---affects mental health. We use Swedish administrative data ($N=576,285$) to link variation in gender composition across classrooms within cohorts to mental health. We find

Economic Challenges for East Timor

The situation in East Timor is turbulent and future growth prospects are indeterminate. This paper discusses the economic challenges facing East Timor. Most inhabitants depend on subsistence farming and there is a need to both modernize agriculture and to foster a modern sector that can generate employment for the growing population. Public expenditures play an important role in this development a

Lena Mattsson : The Window Opens to the World

The book is monograph on the work of Swedish filmmaker and visual artist Lena Mattsson (b. 1966) with an introductory essay by Andersson, and two texts by Wiberg and Nilsson respectively. The book is illustrated with photographs and film stills from the whole of Mattsson's career, but the main focus is on her recent projects.A monograph on the art of visual artist and filmmaker Lena Mattsson, Sweden (b. 1966). The book includes a lengthy essay by Andersson and two brief texts by Wiberg and Nilsson, and is furthermore illustrated with photographs and film stills from the whole of Mattsson's career. Focus is on her recent works, though.

Lessons from the Swedish Experience with Negative Central Bank Rates

Negative interest rates were once seen as impossible outside the realm of economic theory. However, several central banks have recently adopted negative policy rates. The Federal Reserve is coming under increasing pressure to follow suit in the wake of the coronavirus crisis. This paper investigates the actual effects of negative interest rates using the Swedish experience from 2015 to 2019. The S

The Quest for Economic Stability: A Study on Swedish Stabilization Policies 1873–2019

There is a never-ending quest for a stable economy with full employment and low inflation. Economists have suggested and policymakers have experimented with different fiscal and monetary policy regimes since at least the beginning of the industrial revolution. In this paper, we study Swedish stabilization policies through six policy regimes between 1873 and 2019. We focus on discretionary stabiliz

Discontinuous and Continuous Stochastic Choice and Coordination in the Lab

Coordination games have multiple equilibria under complete information. However, recent theoretical advances show that if players are uncertain but can acquire information about a payoff-relevant state of the world, the number of equilibria depends on whether they can implement strategies (stochastic choice rules) discontinuous in the state. We experimentally test these results in a two-player inv

Straffansvar vid atypiska sinnestillstånd

This doctoral thesis examines the attribution of criminal responsibility in Swedish law in cases where the defendant committed an act during an atypical mental state, e.g. psychosis. In nearly all criminal justice systems, a severe mental disorder can activate special rules that excuse or exempt the defendant. Accountability, or the capacity to be responsible, is a fundamental requirement for crim